Lapping block



"F. F. HILLIX LAPPING BLOCK Filed April 19, 1955 2 Sheets-Sheet 1 hwenlor:

Pas-r52 F H/LL/x, I

Aug. 4, 193

v F. F. HlLLlX LAPPING BLOCK Filed April 19, 1935 2 Sheets-Sheet 2 is i L w m 1 H h r]. v

Patented Aug. 4, 1936 UNITED STATES ATE IQE

American Steel and Wire Company of New Jersey, a corporation of New Jersey Application April 19,

10 Claims.

This invention relates to lapping blocks, and more particularly those which are used for grinding and/r polishing relatively hard surfaces, such as metal or glass, whether planed or curved.

In the grinding and/or polishing of relatively hard surfaces, it has heretofore been the practice to use such devices as abrasive wheels, and lapping heads, wherein the surface of the ob- 'ject, or work-piece, is cut by a multiplicity of cutting points which are irregularly shaped. The surfaces obtained by the use of these devices are almost without exception characterized by having an unevenness which is identified by various terms, such as orange peel, grain marks. This condition is dependent, in part, upon the fineness, or coarseness, of the abrasive wheels and/or abrasives employed. The coarser wheels, and abrasives, are used at first, due to their ability to rapidly remove the stock of the surface of the object being ground and/or polished, while the finer wheels, and/or abrasives, are substituted therefor until the desired highfi-nish is obtained.

Among the many disadvantages of using the abrasive wheels referred to, and other lapping devices of the prior art, is that hard particles are continuously being broken oii from the surface of the object being ground and/or polished, which are entrapped between it and the cutting elements, with the result that marring, and scoring, is effected.

As an example, considerable difficulty is experienced in the grinding and/0r polishing of metal working rolls, due to the fact that scoring of the type referred to takes place, and results in a comparatively deep serpentine groove, 'which'may only be removed at great expense.

One of the objects of the present invention is 40 the provision of a novel lapping block which will rapidly produce a surface condition heretofore unobtainable.

Another object is to provide an object of the class described which may be easily and cheaply fabricated, and utilized in such manner that the possibility of scoring or marring is entirely eliminated.

The foregoing and other objects will be apparent after referring to the drawings, in which:

Figure 1 is a plan of an embodiment of the invention.

Figure 2 is a cross-section.

Figure 3 is a plan of a modified form of the in- 55 vention.

1935, Serial No. 17,321

Figure 4 is across-section of the modification of Figure 3.

Figure 5 is a plan of a further modification.

Figure 6 is a cross-section of the modification of Figure 5. 5

Figure 7 is a plan of a still further modification.

Figure 8 is a sectional view on the line VII VII of Figure 7 Figure 9 is a plan of a still further modifica- 10 tion.

Figure 10 is a sectional view on the line XX of Figure 9.

Figure 11 is a sectional view on the line XI XI of Figure 9.

Referring more particularly to the drawings, the numeral 2 designates a block which is composed of any suitable material, preferably nonmetallic and non-hydrous; for instance a durable fiber, or bakelite. This block 2 may be of 20 any suitable shape (being shown in the present instance as rectangular) and is provided with an enlarged aperture 3 which is adapted to retain the cutting element of the invention. This cutting element is shown at 4 and preferably comprises a strip of tin-foil, or other suitable thin metal, which isconvoluted as at 5. These convolutions 5 are so spaced as to provide voids 6 therebetween, and thereof are adapted to protrude. from the recess 3 of the block 2 as indi- 3U cated at 'l. The voids '5 between the various convolutions 5 of the metal strip or tin-foil 4 serve to retain the small particles which are cut off from the surface of the object being ground and/or polished, and thereby eliminate the danger of scoring or marring.

A modified form of the invention contemplates the immersion of the block 2 and its metal strip 4 in a suitable binder, such as bakelite, resinoid, shellac, silicate of soda, waterproof-glue, (such as casein-glue or animal glue), vulcanized rubber, some of the harder waxes, or low meltingpoint solder.

Referring to Figures 3 and 4 of the drawings, a further modification contemplates the provision of a plurality of metal strips 8 which are corrugated, as at 9, to form diametrically opposite contact points I E; and I2. The metal strips 8 may be of varying thicknesses; and experiment has shown that strips of .004 inch thickness are suitable for a roughing cut, while .001 inch is very satisfactory for finishing operations.

The corrugated metal strips 8 are packed into a rectangular recess 3 in the block 2 with alternately disposed straight strips l3 in such manner as to provide voids l4 between the diametrically opposite points It] and 12 of the strips 8 and the surfaces of the straight strips l3. The outer edges of the corrugated strips 8 and the straight strips l3 are adapted to protrude beyond the opening of the recess 3 in the block 2, as shown at [5. The voids l4 serve to retain the small cuttings or chips which are removed from the surface of the object being ground and/or polished. The outer edges [5 of the corrugated strips 8 and straight strips l3 should be periodically brushed and washed off to assure the function of the voids [4 to retain cuttings. If desired, the straight strips l3 may be dispensed with, and the diametrically opposite points [0 and I2 of adjacent strips 8 made to contact each other.

Referring to Figures 5 and 6 of the drawings, still another modification is shown as comprising a plurality of metal strips 16 which are corrugated, as at H, to provide diametrically opposite walls l8 and I9 which are extended longitudinally of the axis of the strips 46 for a short distance. These strips l6 are packed into the recess 3 in the block 2 together with alternately disposed straight strips 20 which contact the diametrically opposite walls l8 and I9 thereof. The relationship of the corrugated metal strips I6 and the straight strips 20 is such as will provide voids 2| therebetween which serve to retain the cuttings mentioned in describing the earlier embodiments of the invention. It is to be understood, however, that the straight strips 28 may be dispensed with and the diametrically opposite walls [8 and IQ of adjacent strips [6 made to contact each other.

Referring to Figures '7 and 8 of the drawings, still another modification is shown as comprising a plurality of strips 23, each of which is longitudinally corrugated, as at 24, and additionally corrugated, at obtuse angles thereto, as at 25. Straight strips 26 are interposed between the strips 23 to prevent them from nesting, and thus providing voids 21.

In Figures 9, 10 and 11, a further modification provides metal strips 28 which are corrugated at an angle with the line thereof, as at 29. A plurality of strips 30 are alternately disposed between the strips 28 but are reversely corrugated with respect to the corrugations 29, as shown at 3|. This form of the invention provides voids 32 for the retaining purposes described.

A suitable loose abrasive is employed between the blocks I and the work-piece in order to facilitate the grinding and/or polishing. This abrasive is preferably used with oil or an emulsion.

While I have shown and described several specific embodiments of my invention, it will be understood that I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of my invention, as defined by the following claims.

I claim:

1. A lapping block comprising a body having at least one recess, and a body of closely compacted metallic strip disposed in said recess with one of its edges protruding therefrom, the thickness of said metallic strip being substantially that of foil.

2. A lapping block comprising a body having at least one recess, and a closely compacted coil of metallic strip material disposed in said recess with one of the edges of said coil protruding therefrom, the thickness of said metallic strips being substantially that of foil.

3. A lapping block comprising a body having at least one recess, and a plurality of metallic strips disposed in said recess with one of the edges of each of said strips protruding therefrom, the thickness of said metallic strips being substantially that of foil.

4. A lapping block comprising a body having at least one recess, and a plurality of metallic strips disposed in said recess with one of the edges of each of said strips protruding therefrom, all of said protruding edges lying-in the same plane, the thickness of said metallic strips being substantially that of foil.

5. A lapping block comprising a body having at least one recess, and a plurality of relatively thin corrugated metallic strips disposed in said recess in such manner that the corrugations of adjacent strips oppose each other, one of the edges of each of said strips protruding from said recess.

6. A lapping block comprising a body having at least one recess, and a plurality of relatively thin corrugated metallic strips disposed in said recess in such manner that the corrugations of adjacent strips oppose each other, one of the edges of each of said strips protruding from said recess and lying in the same plane.

7. A lapping block comprising a body having at least one recess, a plurality of corrugated strips disposed in said recess with one of their edges protruding therefrom, and a flat metallic strip disposed between adjacent corrugated strips with its edges protruding from said recess.

8. A lapping block comprising a body having at least one recess, a plurality of corrugated strips disposed in said recess with one of their edges protruding therefrom, and a flat metallic strip disposed between adjacent corrugated strips with its edges protruding from said recess, the protruding edges of said corrugated strips and the protruding edges of said fiat strips lying in the same plane.

9. A lapping block comprising a body having at least one recess, a plurality of corrugated strips disposed in said recess with one of their edges protruding therefrom, and a fiat metallic strip disposed between adjacent corrugated strips with its edges protruding from said recess, the protruding edges of said corrugated strips and the protruding edges of said flat strips lying in the same plane, and the corrugations of said corrugated strips extending both transversely and longitudinally of their lengths.

10. A lapping block comprising a body having at least one recess, a plurality of corrugated strips disposed in said recess with one of their edges protruding therefrom, and a flat metallic strip disposed between adjacent corrugated strips with its edges protruding from said recess, the protruding edges of said corrugated strips and the protruding edges of said flat strips lying in the same plane, and the corrugations of said corrugated strips extending at substantial 45 degree angles with respect to the longitudinal axes thereof.

FOSTER F. I-HLLIX. 

